Musical instrument and method of



' H. PULLEN May 14, 1940.

MUSICAL INSTRUMENT AND METHOD OF ASSEMBLING THE SAME Original Filed Jan. 26, 1937 2 Sheets-Sheet 1 M PM w H H. PULLEN May 14, 1940.

MUSICAL INSTRUMENT AND METHOD OF ASSEMBLING THE SAME 2 Sheets-Sheet 2 Original Filed Jan. 26, 1937 a wucMoo [Va/7729 71/,

Patented May 14, 1940 UNETEB STATES PATENT OFFICE MUSICAL INSTRUMENT AND METHOD OF ASSEMBLING THE SAME;

Harry Pollen, Easton, Md., assignor to PlaRola Corporation, Easton, Md., a corporation of Maryland 9 Claims.

This invention relates to improvements in musical instruments and method of assembling the same to insure accurate tracking of a perforated music strip over the note openings of an encased harmonica and to provide an inexpensive but effective seal for the ends of the harmonica casing, and it comprises a rigid chassis which carries the music strip spools and harmonica casing in accurate parallel relationship, with the ends of the chassis sealing the ends of the harmonica casing when assembled therewith, and a surrounding housing which constitutes a sound box or resonance chamber, together with other structural improvements for effecting manufacturing economies and permitting quantity production with uniform results; all as more fully hereinafter set forth and as claimed.

The present instrument is an improvement upon that disclosed in Patent No. 1,813,337 of which I am joint patentee, comprising a harmonica mounted in a slotted tubular casing with its note openings exposed to a perforated music strip which is drawn from a spool, across the slotted tracker surface of the casing, and is wound on a receiving spool, so that air blown into the casing and passing out through the harmonica will cause it to play as its note openings are uncovered by the passing perforations in the music strip.

Much difliculty was experienced with prior instruments of this type because in quantity production many of them proved to be imperfect and defective. This was manifested by tearing of the music strips and by their creeping along the tracker surface when the instrument was played, bringing the perforations of the strip into registry with the wrong note openings of the harmonica and resulting in false notes and discord.

I have found that the cause of this defect lay in the mounting and relative positioning of the harmonica casing and the music strip spools. For proper performance their axes must be accurately parallel so that the music strip will be 45 drawn from one spool and wound upon the other with tension applied evenly over its full width, whereby it will be held down to the tracker surface of the harmonica casing and will not be 50 blown away from it when the instrument is played. Furthermore, the harmonica casing must be at right angles to the line of travel of the music strip so that no slack will be produced in the latter and its perforations will register with the proper note openings of the harmonica.

If the parts are not held parallel to each other, the instrument will not play satisfactorily.

It was the practice in prior instruments to mount the harmonica casing and spools in a diestamped sheet metal housing and to support 5 them on the end walls of the housing. The spools were releasably engaged at their ends by spring pressed pintles at one end and by handle means which extended through the housing and engaged the other ends of the spools for selectively rotating them to wind the music strip upon one or the other. The spool supporting ele ments were carried in bushings which projected through holes stamped in the end walls of the housing, either before the sheet metal was bent to box shape or in the course of the die-stamping operation.

In die-stamping processes the sheet metal when bent to shape is spread somewhat under pressure and its opposed walls may not be of exactly the same dimensions as a result. The housing made by such a process was frequently distorted to such an extent that the holes for receiving the spool bushings were out of alignment in the finished product. Not only was this true when the holes were punched in the metal before bending it to box shape, but it also resulted when they were punched after the shaping operation. When holes were separately punched in each end wall with reference to its edges they would consequently be out of aligmnent because of the varying dimensions of the edges. Then, too, the har monica casing which was positioned in the receptacle and attached to its end walls, might be of slightly different length than the distance between the end walls and as a consequence, when it was mounted between them, they would either be bent outwardly to accommodate it or drawn inwardly by the fastening means at its ends. The sheet metal housing had a tendency to 40 weave or to assume a permanent twist which further contributed to misalignment of the music strip spools and the improper relative positions of the parts in adapting itself to strains so imposed upon it.

It was attempted to overcome these difficulties by making the housing of a molded plastic such as Bakelite. The contraction and warping of the plastic in cooling, however, was found to destroy the alignment of the spool supports in its end walls.

My present invention eliminates the defects heretofore encountered by assembling the harmonica casing and spool supports together as a unit which is rigidly braced to maintain the relative positions of the parts, after which the enclosing housing is attached to the chassis, but in such a manner as not to transmit twisting strains to it. I

Not only can the present instrument be assembled with the facility required for quantity production but economical manufacture is fur ther contributed to by the simple means which this assembly affords for sealing the ends of the harmonica casing. Heretofore it was the practice to close the ends of the casing by plugs or diaphragms in order to make it leak-proof before mounting it between the end walls of the boxlike housing. Since these walls were formed integrally with the other parts of the housing, they could not be drawn into tight contact with the ends of the harmonica casing to an extent sufficient to seal it, but inasmuch as my present invention contemplates the use of end plates which are independent of the rest of the housing, these may be drawn tightly into sealing contact with the open ends of the harmonica casing and will thereby effect a tight seal with it before the enclosing housing is attached.

It is accordingly an object of my invention to provide an improved musical instriunent in which the music strip spools and harmonica casing are assembled in accurate relative positions in a rigid chassis which forms a part of a subsequently affixed instrument housing.

A further object of the invention isto provide a rigid chassis in which the harmonica casing and music strip spools are mounted in parallelism between end plates which serve to seal the ends of the harmonica casing and to which a surrounding housing is subsequently attached, with the end walls of the chassis serving as the end walls of such housing.

Other objects and advantages will be apparent from the following description and drawings wherein:

Figure 1 is a perspective view of my improved instrument with the cover open to show the interior assembly.

Figure 2 is a transverse sectional view.

Figure 3 is a sectional view taken along the line 3-3 of Figure 2.

Figure 4 is a longitudinal sectional view taken along the line 4-4 of Figure 3, the mouthpiece and part of the harmonica being shown in full lines.

Figure 5 is a perspective of the assembled chassis.

Figure 6 is a diagrammatic view in transverse section through the casing and harmonica, showing the manner of mounting the latter inv position.

The instrument housing, as shown in Fig. 1, has end walls 10 and l l which also constitute the ends of a rigid chassis for support of the playing mechanism. They are independent of the rest of the housing except for attachment to the side walls l2 and [3 by screws or other fastening means l4 and I5. This permits the end walls to be positioned and spaced accurately from each other irrespective of the fit of -the other parts of the housing. In quantity production it is customary to produce these by die-stamping sheet metal as a result of which the dimensions of the parts may vary considerably.

A bottom plate [6 is fastened to the side walls and a top I! is secured to the wall l3 which is formed in two sections, the upper of which swings outwardly on hinges l8 when the top is opened.

The plates which constitute the walls Hi and i I are drawn into tight sealing engagement with the open ends of a tubular harmonica casing I9 by means of spaced tie rods 20 and 2! upon the threaded ends of which nuts 22 and 23 are received.

The end plates are formed with aligned openings in which bushings 24, 25, 26 and 27 are mounted. Cranks 28 and 29 are journalled in the bushings 24 and 25 of one end plate through which project and terminate in flat ends for engagement with slots in the ends of a pair of music strip spools to rotate the same. The bushings 26 and 27 in the opposed end plate have bores which receive pins Bil and Ill and springs 32 for projecting them into recessesin the opposite ends of the music strip spools. As shown in Fig. 3, either or both of these pins may be formed with a stem 33 which projects beyond the bushing and has a washer 34 attached to it. The washer serves not only to limit inward movement of the pin under influence of the spring when its associated spool is not in place but affords a grip for withdrawing the pin to release the music spool when it is desired to replace it.

The casing I!) has a curved surface in which a series of slots are provided to register with the note openings of a harmonica 35 which is received and fixed in position within it. A slotted gasket 37. interposed between the harmonica and inner wall of the casing, insures a leakproof seal which will prevent the escape of air around the note openings. The casing also has a mouthpiece 38 communicating with its interior and it thereby constitutes an enlarged air chamber into which air is blown to pass out through the harmonica note openings as these are uncovered by the perforations in the music strip drawn across the curved tracker surface of the casing.

A stiff supporting strip 4!] is mounted in the casing Hi to press the harmonica firmly into contact with the gasket 31 and hold it in mounted position. This strip bears at its longitudinal edges on the interior wall of the casing and in its intermediate portion it is pressed against the bottom of the harmonica. The pressure which is exerted by the supporting strip is transmitted directly to the metal side plates of the harmonica rather than to the wood center strip between them. This eliminates the danger of the center strip splitting as it frequently did in prior instrumerits wherein the harmonica was retained by wedges driven into the ends of the casing or by set screws bearing upon the wood strip. The moisture of a users breath causes the wood strip to swell and since in prior constructions no means was provided for relieving pressure on it, the strip frequently split with consequent destruction of the harmonica.

The music strip must travel continuously in contact with the tracker surface in playing an instrument of this type, to prevent its being blown away from the note openings. To this end it is preferable to thread the strip from the feed spool across and around the tracker surface and under the receiving spool in the manner shown in Figs. 1 and 2. This provides the necessary frictional engagement with the tracker surface to hold the strip taut and in contact with the harmonica casing. However, in so compact an instrument the spools lay closely adjacent to the casing and as the diameter of the receiving spool increases when the strip is wound upon it two principal disadvantages are encountered; the area of its contact with the harmonica casing increases as the bulk of the spool becomes larger, because 76 such as to cause it to contact the casing. Both of these results increase the frictional resistance to winding the strip onto the receiving spool and may cause suificicnt tension to tear it. Furthermore, the operation of the crank for rotating the receiving spool becomes increasingly diilicult during' the playing of a piece of music and its operationis likely to become jerky and irregular as a result.

In my present instrument these disadvantages are obviated by mounting the receiving spool at a level higher than the feed spool whereby no appreciable increase in frictional resistance will be encountered when the music strio'is wound upon it.

In assembling the instrument, the harmonica is first inserted in. the tubular casing with the sealing gasket in position around its note openings. As is shown in Fig. l, the casing is then distorted, as by being pressed in a vise, and thereafter the supporting strip s9 is slid into place.-

press the harmonica and gasket closely against the casing wall in registry with the slots 35.

The mouthpiece E8 is then pressed into an opening into a hole previously formed for it and the structure thus far assembled is positioned between the similarly formed plates ill and l l. The tie bars 2'.) and 2| are now extended through the casing and end plates, and before the nuts 22 and 23 are tightened the casing is positioned accurately with respect to the edges of the end plates or to the openings in them by means of a jig. While the parts are accurately positioned in this manner, the nuts on the tie rods are tightened, thereby producing a rigid chassis with the harmonica casing securely held in precise relation to the axes of the openings in which th spool bushings are then mounted.

The sides l2 and 13 of the housing are next attached to the end walls of the chassis. These sides are, conveniently, wood strips to which the bottom I6 of the receptacle is affixed, or they may be formed of sheet metal by a stamping operation in which case they may be integral with the bottom. If it is desired to give all the walls of the housing the same appearance, the wood side walls will be covered by metal plates suitably lithographed or painted.

The instrument housing constitutes a virtually separate structure from the chassis. Thus no strains are imposed on the chassis which would twist or warp it and destroy the accurate position of its parts. The housing functions as a sound box or resonance chamber in which the tonal quality of the music is materially enhanced. The cover when closed serves as a refiecting board against which the sounds issuing from the harmonica are directed and the bottom of the receptacle or housing is formed with a number of enlarged openings through which the amplified music issues.

From the foregoing it will be understood that my invention provides an instrument of inexpensive construction which may be assembled quickly and with the necessary accuracy for satisfactory playing, and that it aifords manufacturing economies while at the same time it constitutes a more rigid and durable construction.

What I claim is:

1. A musical instrument of the player type having a rigid chassis comprising separate end plates formed with spaced openings, a slotted harmonica casing closed at its ends by said plates and accurately positioned with respect to the aforesaid openings in its assembly therewith, tie means for drawing the plates into tight, sealing engagement with the ends of the harmonica casing, spool supports received in the openings in said plates whereby a pair of spools is positioned in the chassis accurately with respect to the harmonica casing, and a bottom, sides and top surrounding said chassis to form, with the said plates as end walls, a housing or resonance chamber for the instrument.

2. A musical instrument of the player type having a rigid chassis comprising separate and plates with similarly spaced openings therein, a slotted harmonica casing, a mouthpiece communicating therewith, a harmonica positioned therein with its note openings in registry with such slots, a flat surfaced strip supporting the harmonica by contact with its metal side pieces and by engagement with the inner wall of said casing, tie means for drawing said end plates into tight, sealing contact with the ends of the casing when positioned accurately with respect to the openings therein, bushings mounted in the openings of said plates, spools supported in said bushings, means for rotating the spools, a perforated music strip adapted to be wound from one spool to the other and to pass over the slotted surface of the harmonica casing, and a bottom, sides and top attached to said chassis to form, with the end plates thereof, an enclosing housing for the instrument.

A musical instrument of the player type comprising a rigid chassis having end plates and a tubular harmonica casing extending therebetween. said end plates being preformed with aligned openings for mounting music spool supports, a harmonica within said casing, a projecting mouthpiece on said housing, a bottom,

sides and top assembled with the end plates of said chassis to form an enclosing housing through which said mouthpiece extends, spools within said housing and carried by said chassis in parallel relation to the harmonica casing, means for selectively rotating said spools, and a perforated music strip adapted to be wound from one spool to the other to pass over the harmonica casing.

4:. A musical instrument of the player type comprising a rigid chassis having end plates and a tubular harmonica casing extending therebetween, said end plates being preformed with aligned openings for mounting music spool sup ports, a harmonica within said casing, a projecting mouthpiece on said housing, a bottom, sides and top assembled with the end plates of said chassis to form an enclosing housing through which said mouthpiece extends, spools within said housing and carried by said chassis in parallel relation to the harmonica casing, means for selectively rotating said spools, and a perforated music strip adapted to be wound from one spool to the other to pass over the harmonica casing, the spool which receives the strip during playing of the instrument being higher than that from which the strip is drawn to minimize the tension and snubbing eifect thereon as the diameter of the receiving spool increases from the increasing windings of music strip thereon.

5. A player instrument comprising a harmonica, a tubular casing for said harmonica with openings in registry with the harmonica note openings, a pair of end plates formed with aligned openings, tie rods passing through certain of such openings and fastening means therefor for drawing said plates into sealing contact wtih the ends of said housing, spool holding means mounted in other of such aligned openings, the said end plates forming ends of said tubular casing to which they are attached, the said spool holding means being located adjacent the tubular casing and with their axes in diiierent planes whereby a perforated music strip drawn from the feed spool across the openings of the tubular casing and onto the receiving spool will not bind and tear as the diameter of the receiving spool increases.

6. A player instrument composed of separately formed end plates with aligned openings therein, a tubular casing with note openings therein and with its ends abutting said end plates, tie rods extending through said casing and between said end plates and means on said tie rods for tightly drawing said end plates into sealing contact with the ends of said casing, a harmonica mounted in said casing in registry with the note openings therein, a supporting strip inserted in said casing to press the harmonica into sealing contact with the note openings of the casing and supported along its longitudinal edges on the interior walls of the casing, music roll supporting spools adjacent the said casing and handle means for rotating the spools to feed the music strip from one to the other, the latter spool being mounted at a higher level than the feed spool so that as the music strip is wound thereon and its diameter consequently increased it will not be drawn across the casing and onto the spool at an abrupt angle such as would result in undue increase in frictional resistance.

'7. In the method of assembling a musical instrument of the player type which comprises forming a pair of end plates with aligned openings, positioning such plates at the ends of a tubular harmonica casing and aligning the same therewith by a jig, drawing said end plates into sealing engagement with the harmonica casing by tie means to produce a rigid chassis, assembling spool supporting members in the respective openings of said end plates whereby the spools will be accurately positioned with respect to the harmonica casing so that a perforated music strip drawn from one to the other across the casing will bear evenly upon it and in registry with the harmonica note openings, and attaching side panels, a bottom and top to the chassis to form an enclosing housing for the completed instrument.

8. The method of assembling an instrument of the player type which comprises inserting a harmonica into a tubular casing with its note openings in registry with corresponding openings in the casing, applying pressure to the tubular casing to distort it and enlarge it transversely, inserting a supporting strip into said casing under the harmonica, whereupon by release of pressure upon the casing it will resume its normal shape and will engage the longitudinal edges of the supporting strip to press the harmonica into sealing engagement with the casing, in registry with the respective note openings, whereby the harmonica will be held against accidental displacement.

9. The method of assembling an instrument of the player type which comprises mounting a harmonica within a tubular casing with its note openings in registry with corresponding openings in the casing, inserting retaining means in the easing to prevent accidental displacement of the harmonica therein, positioning separate plates at the ends of the casing so that pre-formed holes therein are in accurate alignment and their axes are parallel to that of said casing, drawing the plates as so aligned into sealing contact with the ends of the casing to produce a rigid chassis, mounting spools for a perforated music strip between said plates on either side of and parallel to the said casing, and attaching a bottom, top and sides to the chassis to form, with the end plates thereof, an enclosing housing and resonance chamber through which a mouthpiece extends from said harmonica casing and from the exterior of which handle means project for draw ing the music strip from one spool to the other to track accurately across the openings in the harmonica casing.

HARRY PULLEN. 

